Image-capturing devices, such as scanners, may be configured to scan opaque media and at least partially transparent media, such as transparencies, photo-negatives, slides, etc. When scanning opaque media, light is typically reflected off an image on the surface of the opaque media and onto a sensor that converts the received light into a signal containing data corresponding to the image on the surface of the opaque media. Transparent media are scanned by passing light through the transparent media and onto a sensor that converts the light into an image signal containing data corresponding to an image on the surface of the transparent media.
Some conventional scanners include a separate light source to backlight the image on the transparent media. The backlight source may be included in a separate transparent media adapter or may be integrated within the scanner equipment, such as in the cover that overlays the scanner platen. However, the backlight source and its implementation hardware add complexity and cost to the scanner. Still other techniques for scanning both transparent and opaque documents include, for example, eliminating the backlight source and collecting the light from the light source used for scanning the opaque media and reflecting the light through the transparent media. However, such techniques require implementation hardware that adds complexity and cost to the scanner.